Oil burner



March 14, 1967 A. B. CHADWICK ETAL 3,309,027

OIL BURNER Filed Dec. 18, 1964 INVENTORS Abraham 8. Chadwick Y Jock N.Tuflerrow ATTORNEY United States Patent ()fllice 3,309,027 Patented Mar.14, 1967 3,309,027 (BIL BURNER Abraham B. Chadwick, .iefiersontown, andJack N. Tutterrow, Louisville, Ky., assignors to American Radiator &

Standard Sanitary (Iorporation, New York, N.Y., a corporation ofDelaware Filed Dec. 18, 1964, Ser. No. 419,474 2 Claims. (Cl. 239-406)This invention relates to new and useful improvements in oil burners andmore particularly to a flame retention burner.

With conventional burners, a combustion chamber is required to assureburning any of the oil that escapes the air pattern. By proper design ofburners firing with flame retention characteristics, all the oil spraymay be confined within the air pattern thus eliminating the need for acombustion chamber. For wet base boilers th elimination of theinsulating effect of the combustion chamber may result in an increase ofapproximately twenty percent in the boiler output. In addition, flameretention firing greatly improves flame stability thus eliminating thepulsation problem commonly obtained with conventional burners.Accordingly, flame retention burners are able to increase boiler output,improve flame stability, and eliminate the need for a combustionchamber.

Flame retention firing is accomplished by producing a more rapid mixingof the oil spray with the combus- 'tion air such that a proper air-fuelratio for combustion is attained at the end of the air tube. Accordingto the present invention this rapid mixing is accomplished by increasingthe air turbulence by a spinner attached to the inner assembly. Employedwith the burner is a nose tube which helps establish the origin of theflame at the face of the spinner. The nose tube creates a low pressurearea with eddy currents at the tip of the spinner blades. This in turnhelps establish the origin of the flame and results in improved flamestability.

Also according to this invention an annulus is employed to provide airat the periphery of the flame to insure that the oil spray is confinedwithin the air pattern. The spinner and annulus are fabricated as a unitto insure concentricity of the annulus while the mating nose tube isutilized -to maintain spinner centering with respect to the air tube.This improved concentricity gives a more symmetrical flame with lesssmoke.

Accordingly, it is an object of this invention to provide an oil burnerhaving an increased output and improved flame stability.

Another object is to provide a burner which permits elimination of theusual combustion chamber thereby improving the heat transfer.

Another object is to provide means for assuring concentricity of the airspinning plate member to the burner air tube.

The foregoing and other objects will become apparent from the followingdescription of the invention.

In the accompanying drawings to be taken as a part of thisspecification, there is fully and clearly illustrated a preferredembodiment of the invention, in which drawings,

FIGURE 1 is a view in longitudinal vertical section through the air tubeportion of a pressure type oil burner, and

FIGURE 2 is an end view of the burner, looking at its discharge end.

Before explaining the present invention in detail, it is to beunderstood that the invention is not limited in its application to thedetails of construction and arrangement of parts illustrated in theaccompanying drawings, since the invention is capable of otherembodiments and of being practiced or carried out in various ways. Alsoit is to be understood that the phraseology or terminology employed isfor the purpose of description and not of limitation.

Referring to the drawings by characters of reference, the numeral 1designates an air tube which is a cylindrical metal casing extending atits inlet end 2 from an air blower or fan which is not shown as theconstruction is well understood in the art. The forward or front endportion of the air tube 1 terminates in a nose tube membet 3 which fitson the end of the air tube 1 and is secured thereto such as by thefasteners 3a. The nose tube member 3 has its discharge end portion 4 ofreduced diameter relative to the air tube 1 providing a forwardextending cylindrical wall and an annular shoulder 5.

Within the air tube 1 is the oil supply tube or pipe 6 which leads fromthe usual fuel pump, not shown, and terminates at its discharge or frontend in a spray nozzle 7. The pipe 6 is supported intermediate its endsby a plate member 8 having an aperture therethrough through which thepipe 6 extends. Also extending through apertures in the member 8 are apair of ignition electrodes 9 and 10 terminating just forward of andabove the nozzle 7.

The plate member 8 supports or carries an air spinning plate or spinner11 having an outwardly and rearwardly flaring circumferential flange oredge portion 12. The plate members 8 and 11 are spaced apart byequispaced tubular spacers 13 and are secured together by bolts 14passing through the plate members and the tubes. The nose tube shoulder5 receives the flange 12 which abuts thereagainst, thus centering theplate member 11 and the unit assembly supported therewith relative tothe nose tube wall 4. A foot member 15 rests on the inside bottomsurface of the air tube 1 and supports the plate member 8.

The spinner 11 has an annular series of apertures 16 for the dischargeof ahollow cylindrical air stream from the air tube 1. The elongatedcurved apertures 16 are spaced concentrically inwardly from the fiange12 and wall 4. Each of the apertures 16'is subtended by a vane or blade17 formed by bent out portions of the plate member 11. Each vane isbounded by a radial slot 18 and by end slots which define the apertures16.

An opening 19in the spinner 11 surrounds the nozzle 7 which terminatesclosely adjacent thereto, for example one quarter inch from the plane ofthe spinner 11. Thus the blades 17 impart a swirling motion to the airexiting from the air tube 1 and the spraying oil is thus surrounded by aprimary air stream into which the oil droplets discharge to mixtherewith for ignition by the electrodes 9 and 10. The ignited fuelmixture burns adjacent the discharge or front face of the spinner 11.

Due to the air flowing through the apertures 16, a cylinder of airissues therefrom thereby providing air at the periphery of the flame toinsure that the oil spray is confined within the cylindrical airpattern. Although the apertures 16 do not define a full and completeannulus, the blades 17 adjacent thereto gives the air a swirling actionwhich will pull the air issuing from the apertures 16 around so that itwill form a full cylindrical sheet of air around the flame.

With the construction as defined above, the cylindrical sheet of airwill be of even force and magnitude all around because the spinner andapertures 16 are fabricated as a unit. Thus, even if the burner assemblybecame slightly misaligned in the air tube 1, the apertures 16 wouldstill provide a uniform cylindrical curtain of air to confine the oilspray. This is contrasted to a more conventional construction where aspinner which does not have apertures 16 becomes misaligned in the airtube thereby providing an uneven gap about the periphery of the spinnerrelative to the air tube, thereby resulting in an uneven air pattern.

In the present invention the flanged peripheral edge 12 of the spinnermates with the shoulder of the nose tube to maintain centering of thespinner withrespect to the air tube.

It will be observed that there willbean outwardly directed radialcomponent of air at the ends of the spinner blades. This outwardlydirected air flow hits the nose tube 4 and is redirected towards thecenter of the nose tube. As this air hits the nose tube it starts torecirculate setting up eddy currents which create a low pressure tendingto pull oil droplets radially outwardly from the nozzle 7. Thus the lowpressure resulting from these eddy currents pulls the oil dropletsthrough a turbulent area in front of the spinner 11 so that there isthorough mixing of air and oil resulting in combustion taking placeacross the full face of the spinner. V

From the above description it will be seen that the apertures 16 providea cylindrical curtain of air in which the oil spray is confined and thatthis cylindrical curtain of air is even all around since the apertures16 are made in the spinner plate. spinner plate mates with the shoulder5 of the nose tube to insure the concentricity of the spinner relativeto the nose tube. Further the nose tube functions to create a reducedpressure adjacent the inner periphery thereof tending to pull oil dropsfrom the oil spray thereby establishing origin of the flame across theface f the spinner.

While the instant invention closed with reference to the particularembodiments thereof, it will be readily understood that variations andmodifications thereof may be made without departing from the spirit andscope of the instant invention.

What is claimed is:

1. In an oil burner, an air tube, fuel nozzle means in said air tube, anose tube at the discharge end of said air tube having a diameter lessthan that of the air tube to thereby provide an annular shoulder, aspinner plate having a substantially planar peripheral flaring portionseating against such shoulder so as to center said spinner platerelative to said nose tube, said spinner plate havingradially extendingvane members and cooperating openings to spin air discharging therefrom,said spinner plate also having a series of apertures radially out boardof said vanes forming a substantial cylindrical air discharge opening,said apertures providing a cylindrical curtain of air which confines theoil spray issuing from said fuel nozzle, said nose tube having acylindrical wall portion extending forwardly of said spinner plate, saidwall portion providhas been illustrated and dis-- The flanged periphery12 of the ing a surface to defiect radial components of air leaving saidvane members towards the center of the nose tube thereby creating eddycurrents and creating a low pressure adjacent the inner surface of thenose tube tending to pull oil droplets radially outwardly from the fuelnozzle through the turbulent area in front of the spinner plate so thatthere is thorough mixing of air and oil resulting in combustion takingplace across the face of the spinner plate.

2. In an oil burner, an air tube, a fuel nozzle means in said air tube,a nose tube, at the discharge end of said air tube having a diameterless. than that of the air tube to thereby provide an annular, shoulder,a spinner plate having a substantially planar diameter less than thatofsaid air tube but greater than that of the reduced internal diameter ofthe nose tube, said spinner plate having a peripheral flaring portionseating against such shoulder so as to center said spinner platerelative to said nose tube, said spinner plate having radially extendingvane members and cooperating openings to spin air:discharging therefrom,said spinner plate also having a series of apertures at the radial endsof said vanes forming a substantial cylindrical air discharge opening atthe radial end of said vanes, said apertures providing a cylindricalcurtain of air which confines the oil spray issuing from said fuelnozzle, said nose tube member having a cylindrical wall portionextending forwardly of said spinner plate, said wall portion providing asurface to deflect radial components of air leaving said vane memberstowards the center of the nose tube thereby setting up eddy currents andcreating a low pressure adjacent the inner surface of the nose tubetending to pull oil droplets radially outwardly from the fuel nozzlethrough the turbulent area in front of the spinner plate so that thereis thorough mixing of air and oil resulting in combustion taking placeacross the face of the spinner plate.

References Cited by the Examiner UNITED STATES PATENTS 351,390 10/1886Mitchell 239-406 1,434,406 11/1922 Purnell 239-403 2,347,594 4/1944 DeLin 239-406 FOREIGN PATENTS 205,892 10/1923 Great Britain.

EVERETT W. KIRBY, Primary Examiner.

1. IN AN OIL BURNER, AN AIR TUBE, FUEL NOZZLE MEANS IN SAID AIR TUBE, ANOSE TUBE AT THE DISCHARGE END OF SAID AIR TUBE HAVING A DIAMETER LESSTHAN THAT OF THE AIR TUBE TO THEREBY PROVIDE AN ANNULAR SHOULDER, ASPINNER PLATE HAVING A SUBSTANTIALLY PLANAR PERIPHERAL FLARING PORTIONSEATING AGAINST SUCH SHOULDER SO AS TO CENTER SAID SPINNER PLATERELATIVE TO SAID NOSE TUBE, SAID SPINNER PLATE HAVING RADIALLY EXTENDINGVANE MEMBERS AND COOPERATING OPENINGS TO SPIN AIR DISCHARGING THEREFROM,SAID SPINNER PLATE ALSO HAVING A SERIES OF APERTURES RADIALLY OUT BOARDOF SAID VANES FORMING A SUBSTANTIAL CYLINDRICAL AIR DISCHARGE OPENING,SAID APERTURES PROVIDING A CYLINDRICAL CURTAIN OF AIR WHICH CONFINES THEOIL SPRAY ISSUING FROM SAID FUEL NOZZLE, SAID NOSE TUBE HAVING ACYLINDRICAL WALL PORTION EXTENDING FORWARDLY OF SAID SPINNER PLATE, SAIDWALL PORTION PROVIDING A SURFACE TO DEFLECT RADIAL COMPONENTS OF AIRLEAVING SAID VANE MEMBERS TOWARDS THE CENTER OF THE NOSE TUBE THEREBYCREATING EDDY CURRENTS AND CREATING A LOW PRESSURE ADJACENT THE INNERSURFACE OF THE NOSE TUBE TENDING TO PULL OIL DROPLETS RADIALLY OUTWARDLYFROM THE FUEL NOZZLE THROUGH THE TURBULENT AREA IN FRONT OF THE SPINNERPLATE SO THAT THERE IS THROUGH MIXING OF AIR AND OIL RESULTING INCOMBUSTION TAKING PLACE ACROSS THE FACE OF THE SPINNER PLATE.